Even though divine and supernatural theology relies
on the divine light and on principles revealed by God, still, because it
is perfected by human discourse and reasoning, it is aided as well by truths
known by the natural light. And it uses those truths as helpers and,
so to speak, instruments in perfecting its own discourses and in illuminating
divine truths.

Now among all the natural sciences, the one
that ranks first of all and goes by the name of First Philosophy is especially
useful to sacred and supernatural theology. This is so, both because
it comes closest of all of them to the cognition of divine matters, and
also because it explains and confirms those natural principles which comprehend
all things in general and which in some sense support and undergird every
doctrine.

For this reason, despite the fact that I have
been engaged in working out and publishing more important commentaries
and disputations in sacred theology, I have been forced to interrupt that
work for a while (or, rather, slow it down), in order at least to review
and enhance at a later time what I had worked out and publicly taught in
my more youthful years concerning this natural wisdom--so that for public
benefit it could be shared with everyone.

For when these metaphysical doctrines
would come up in discussions of the divine mysteries--doctrines that are
such that without a knowledge and understanding of them it is hardly, or
not at all, possible to discuss those higher mysteries in a suitable manner--I
was often forced to mix in less sublime questions with divine and supernatural
matters (which my readers find unwelcome and not very useful), or else,
in order to avoid this problem, I was forced to briefly propound my own
opinion on these matters and to demand from my readers sheer faith, as
it were, in those opinions. This was troubling to me and could have
justifiably seemed importunate to them as well. For these metaphysical
principles and truths fit together with theological conclusions and arguments
in such a way that if one takes away knowledge and complete understanding
of the former, then knowlege of the latter must likewise be greatly undermined.

Therefore, induced by these considerations,
as well as by the urging of many, I have decided to write this work, in
which I bring together all these metaphysical disuputations in accord with
the method of teaching, which is more appropriate for the comprehension
of these matters as well as for brevity, and which better serves revealed
wisdom. For this reason, it will not be necessary to distribute or
partition this work into many books. For all the matters which are
proper to this doctrine, or which belong to the subject under the concept
which is studied in this doctrine, can be included and exhausted in a small
number of disputations. But we will cut out, as foreign to the present
doctrine, matters that pertain to pure philosophy or to dialectic (on which
other metaphysical authors tarry at length).

Now before I begin to talk about the subject
matter of this doctrine, I will first, with God as my protector, examine
wisdom or metaphysics itself, and its object, usefulness, necessity, attributes
and roles.